Fasteners for use with honeycomb or sandwich panels are described in U.S. Pat. No. 3,339,609, entitled “Floating Nut Insert”, U.S. Pat. No. 3,884,006, entitled “Sandwich Panel Insert”, U.S. Pat. No. 4,846,612, entitled “Sandwich Panel Fastener” and U.S. Pat. No. 5,082,405, entitled “Potted Insert For Honeycomb Panels”.
FIGS. 1 and 2 show a prior art fastener assembly for use with a honeycomb panel. The prior art fastener assembly utilizes a stud 1, spring 2, insert 3 and cross pins 4 and 5. Cross pin 4 is frictionally inserted into bore 6 and cross pin 5 is frictionally inserted into bore 7. In order to use this fastener assembly, the user or installer first removes the cross pins 4 and 5 from bores 6 and 7, respectively. Next, the user cements insert 3 to the honeycomb panel using any of the techniques known in the art. After the cement hardens, the user inserts the stud 1 through the spring 2 and then inserts the stud 1 and spring 2 into the insert 3. The user applies force to the stud 1 in order to compress the spring 2. This causes the stud 1 to longitudinally move within the passage of the insert 3 so that bores 6 and 7 become exposed as shown in FIG. 2. The user then reinserts cross pins 4 and 5 into bores 6 and 7, respectively. The process of removing cross pins 4 and 5 from the bores 6 and 7, respectively, and then re-installing the cross pins 4 and 5 after the insert 3 is cemented to the honeycomb panel is a time consuming process. Furthermore, in such a process, it is very easy to drop or mishandle the relatively small-sized cross pins 4 and 5 while trying to reinsert them into the bores 6 and 7, respectively.
Accordingly, there is a need for a new fastener for use with honeycomb or sandwich-type panels that eliminates the problems associated with the prior art fastener assembly shown in FIGS. 1 and 2.